Tuesday, September 30, 2014

Yaupon, Ilex vomitoria, is a native holly to the southeastern portions of the United
States. It is a dioecious species, the
distinction between male and female visible by berry production, which may grow
as high as 8 m (26 ft), but has been readily cultivated for residential
landscapes. While the berries are poisonous to humans, many wildlife species, including songbirds and small mammals, readily consume them. The highly
adaptable and tolerant shrub is often used as a hedge species, but perhaps its
most interesting aspect is that it is the only native plant that produces
substantial amounts of caffeine. The amount of caffeine has been
shown to decline with age of the leaves, shade, and latitude, and certain cultivars have more caffeine variation. The preparation of the leaves for the tea can also impact the amount of caffeine present.

Yaupon has a very rich history with Native American tribes. It was brewed into a tea-like beverage known as Black Drink which that link provides far more information (and sources). The link is simply my in-depth post on Google+ from the week before about the history of it. The comments also mention preparation, taste, antioxidant properties, and how it isn't actually a drink that causes vomiting.

Sorry for lack of posts last week. I went on vacation, but I'm back now. Thursday will be another original post with some photography I'm a bit proud of from earlier this month.

Thursday, September 18, 2014

The Crimson Patch butterfly may be found as far north as Texas and southeastern New Mexico, but is more common through Central America down to Colombia. While there are several broods in Texas, it can be found year around in the tropics. The larvae feed on scrubby plants within the Acanthaceae family which includes flame acanthus and firespike. As early instars, the caterpillars feed as a group, an aggregation, but become solitary during the fourth instar stage. The adults feed on the nectar of a variety of flowers.

Tuesday, September 16, 2014

The Delaware skipper may be seen in parts of eastern North America from Canada down through El Salvador. They are found in open areas, particularly wet ones, such as marshes, prairies, fields, and residential areas. As a type of grass skipper, the larvae feed mostly at night on grasses and sedges including big bluestem, switchgrass, and wooly beard grass. The larvae often make shelters of the leaves as they eat them. The adults drink nectar from many flowers including milkweeds, mountain mint, marsh fleabane, sweet pepperbush, buttonbush, thistles, and pickerelweed. In the north, the Delaware skipper has only one brood a year whereas further south it can be more than two per year.

Thursday, September 11, 2014

The brown-throated three-toed sloth is one of only four species of three-toed sloth, and one of the only two three-toed sloths that are not endangered. They weighing between 2.25 to 6.20 kg (4.96 to 13.7 lbs) and have a body length between 413 to 700 mm (16.3 to 27.6 in). Their forelimbs are longer than the hind limbs As they spend the majority of their time in the trees, their grip is strong and their three digits have long, curved claws. Compared to the rest of the body, the head is smaller and the tail stumpy. The coarse, thick fur has longitudinally grooved strands to allow for green algae to grow which provides as camouflage. Other organisms found within the grooves of sloth fur include cyanobacteria and diatoms while moths, beetles, cockroaches, and nematode roundworms have been found in other parts of their fur. Male brown-throated three-toed sloths have an orange-yellow patch with a brown stripe through the middle between the shoulders. Unlike most mammals, sloths have nine cervical vertebrae instead of seven allow greater mobility of the head. They are active during both the day and the night, but sleep the majority of the time.

Sloths are a neotropical animal that live and flourish on a steady diet of tree leaves, shoots, and fruit. Often a sloth will remain within a tree for days and may have a preferred tree. With a difficult to process diet full of tough cellulose and potential toxins, their digestive system is slow. The large fluctuations of their body temperature can also hinder digestion which causes sloths to practice thermoregulation similar to reptiles. Due to such slow digestion, it may take several days or more for food to pass through the gut of a sloth, and waste eliminate averages once a week or less. Still, sloths are adapted for the diet of foliage with the stomach containing complex pouches that separate batches of food in different stages of digestion. Sloths have also been observed to specify which foliage to consume with pregnant females seen choosing the easier to digest Lacmellea panamensis when possible. They will also choose spots to sleep where they can bask to aid in digestion, but without getting too overheated.

Thursday, September 4, 2014

Cassin's finch is a small rosy-tinged songbird found within the mountains of western North America. Though similar in appearance to house finches and purple finches, Cassin's finch is larger with whiter bellies, peaked head shape, and thick, straight-edged bill. While both male and female Cassin's finches have thin, white eyerings, males are more rosy with an intense red crown whereas females and immatures are more brown and white. Their range and environment also differ with Cassin's finch prefering conifer forests. They are semicolonial with nests sometimes built within close proximity to each other, but often it is only tolerated if nesting time is far enough apart. While their diet is mostly of seeds, insects and fruit are also consumed. They are categorized as a Near Threatened species, but the factors leading to population decline have not yet been identified.

Tuesday, September 2, 2014

Once upon a time, close to 40 percent of the birds on the North American continent were Passenger pigeons. Their massive flocks would block out the sun for hours. Their flapping wings would create a chill far below. Their flight would create a roar of thunder. Within only decades their numbers decreased from billions to none.

Passenger pigeons had been found from far south Texas up through Canada, encompassed the Midwest all the way to the east coast. Their migration route traced along the Ohio River, and their greatest nesting density was within New England and along the Great Lakes. Their massive nesting sites, the largest recorded taking up to 850 square miles, often destroyed trees and coated the forest floor with inches upon inches of waste. So many pigeons could be found in some sites that there were birds sitting upon birds. The grounds nearby looked swept as the twigs and branches were gathered for nests. Within the nest laid either one or two eggs, a number still debated as evidence during the time were simple accounts from various sources.

Passenger pigeons fed on a variety of plants, but their preference was for hard mast such as beechnuts and acorns. The young were fed pigeon milk, the sloughed off lining of the crop. The pigeons themselves fed a number of species including black bears, bobcats, owls, hawks, wolves, and skunks. Passenger pigeons also fed many Native American groups, some relying on them far more than others.

The understanding of the role and connection the Passenger pigeon played in its ecosystem is limited by lacking evidence and data. It is likely they played a great part in the spread of mast trees due to their diet preference and large migration. White oak in particular, a favored acorn, is the dominant oak along much of the eastern United States where Passenger pigeons were concentrated. Canebrakes, ecosystems of American bamboo, were probably encouraged by the pigeons who opened the canopy and fertilized the ground with their droppings. The decline of the American burying beetle is also possibly linked to passenger pigeons as their primary carrion source may once have been the pigeons. With their demise, the beetle has had to find other sources of less abundance. Though the beetle still exists, the once-widespread scavenger is limited to a few Oklahoma counties and two islands off Rhode Island.

In the early years of settlement, Passenger pigeons were one of the principal food sources that kept colonies alive and thriving. They were easy to catch, numerous, and a reliable source of food when crops weren’t ready for harvest. As colonies stabilized and populations grew, the Passenger pigeon went from savior from starvation to dietary mainstay to sport, hobby, and a nuisance. Landowners feared them for ruining agriculture and jeopardizing timber holdings. Hunters shot them for simple fun and money.

Hunters developed a number of techniques for catching Passenger pigeons, but one such technique brought about the common phrase stool pigeon. A single bird was caught live and its eyes sewed shut. Most often, it was manipulated by string then by the hunter to look as if it were peacefully feeding as to encourage others to arrive. Once down, a net would be thrown over the flock. A single shot from a shotgun brought down handfuls. One record of hunting at a nesting site in Petoskey, Michigan recorded around 50,000 birds killed a day for months. So many Passenger pigeons were available that they were a cheap target to use as live targets in shooting galleries and skeet shooting contests.

The number of Passenger pigeons dwindled and no laws were around to protect them. A few attempts were made, but they were either limiting or too late. Contrary to popular thought, research shows that colonial nesting birds are some of the most vulnerable to extinction. It can be driven through the Allee effect where inverse density dependence is defined as a positive relationship between population density, survival, and reproduction. In other words, low population densities cannot support survival. Even though tens of thousands of Passenger pigeons remained when hunting started to die down, their survival relied heavily on being a vast colonial species. For that species, even that number was too few, and compounded with habitat destruction, their extinction was inevitable.

The last two Passenger pigeons to exist were Martha and George. They resided in the Cincinnati Zoo in the early 1900s with a small flock, and were soon the sole survivors by 1909. By 1910, George died to leave Martha as the last known living Passenger pigeon. She stayed on exhibit for her remaining four frail years where many flocked to see her. Still, her treatment was cruel by the crowds who would throw sand at her to make her walk, and her cage was often roped off. On September 1, 1914, her crumpled body was discovered by the keeper. On that day, the Martha died and the Passenger pigeon was officially an extinct species.

Part of the demise of the Passenger pigeons was the lack of protection, but they are one of the driving forces for laws that now exist. In the late 1800s, the Lacey Act was established as an attempt to help the Passenger pigeons. It prohibits illegally obtained game to be shipped across state boundaries, and it helps enforce wildlife protection laws. In the case of Geer v. Connecticut, the U.S. Supreme Court upheld that states hold wildlife in trust for their people and has the power to ensure harvested game is kept for their benefit. The Migratory Bird Treaty Act of 1918 is the key law to protection of native avian species. It protects all parts of native birds to the fullest degree. By federal law, even today, anything that once belonged to a native bird including, but not limited to, live birds, skins, feathers, eggs, and nests, are illegal to possess without a proper permit. In the early 1970s, more laws were enacted and toughed including the Clean Air Act, Clean Water Act, National Environmental Policy Act, and the Endangered Species Act mainly in response to Silent Springs by Rachel Carson that pointed to other threats to wildlife, in particular DTT and other pesticide use.

While mankind has learned since the extinction of the Passenger pigeon, it is still a question of whether we have learned enough. A report from the International Union for Conservation of Nature in 2010 announced that 30 percent of amphibians, 21 percent of mammals, reptiles, and fish, and 12 percent of birds are all at risk of extinction. Across the world, 131 mammals, 23 coniferous trees, 15 reptiles, 217 birds, and 208 amphibians face imminent extinction according to the Alliance for Zero Extinction. Threats to survival include habitat loss, global warming, pollution, and introduction of non-native species in various parts of the world. Whether or not we are in the early to mid-stages of the sixth great extinction event on the planet has yet to be determined, but if nothing is done, it will be a guarantee.

This post is a direct copy from my original Google+ post from yesterday to mark the centennial of the extinction of the passenger pigeons. A few notes of additional information, particular references, are on that post. My previous passenger pigeon post on this blog can be found here. The only other information of particular importance is mention of the wonderful panels provided by Project Passenger Pigeon. The pdf files of the displays are available for use at the link provided.

The Short: I love photography. I love nature. I love all science. You will see posts from me relating to one or all of these topics. There may also be a sprinkling of posts related to general humor, love of books, video games, art, and/or music as well.